You can't talk about Duty Cycle without talking about component temperature. You can run something at 100% duty cycle forever if you can keep the temperature within the ratings of the components.

So, Joe WB9SBD, you can certainly do a 60 minutes On, 60 minutes Off duty cycle if you can keep the components cool.

73, Carey, WB4HXE

On Thu, Aug 13, 2020 at 5:16 PM Frank Donovan <donovanf@...> wrote:

Hi Dan,

FT8 is 100% duty cycle during the entire duration of its 12.6 second transmission.

FT8 is not USB.   Your transceiver is set to USB only so it can translate

the FT8 signal generated by your sound card to selected ham bands.

Think of your transceiver as a mixer with a filter on the output so you

don't get two sidebands from the mixer.

73

Frank

W3LPL

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From: "d_ziolkowski" <dan.ziolkowski@...>
To: main@wsjtx.groups.io
Sent: Thursday, August 13, 2020 8:58:10 PM
Subject: Re: [WSJTX] Duty cycle question

But--- a CW signal is 100% carrier. 

FT8 is USB , little to no carrier.

Think AM vs SSB.

Dan KC2STA

On Thu, Aug 13, 2020 at 4:29 PM Joe WB9SBD <nss@...> wrote:

How narrow is a dead carrier? a LOT smaller than 50 hz, so how long can your rig like a CW Key be pressed down and held?

Joe WB9SBD

The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com

On 8/13/2020 2:14 PM, d_ziolkowski wrote:

Hello all=

We have all been educated that due to the high duty cycle of FT8, it is wise to not run full power of you rig to avoid burning up the finals. 

My question relates to the effect of the transmitted bandwidth, which in FT8 is 50HZ, has on the actual power loading of the finals. 

Since when transmitting a 50Hz signal via a transmitter capable of about 2Khz or so, would this , in effect , very lightly load the finals, even at full power?

Thanks

Dan KC2STA

--

Dan Ziolkowski KC2STA
SKCC #4290T
Ubuntu LINUX

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Carey Fisher

careyfisher@...

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73, Carey, WB4HXE